Conventionally, a memory system including a nonvolatile memory such as a flash memory as a storage memory is known. The memory system stores one or more pieces of translation information therein. Each piece of translation information indicates a correspondence between a logical address and a physical address. That is, each piece of translation information maps a location in the nonvolatile memory on a logical address. The memory system updates corresponding translation information in response to writing data of which a location is designated by a logical address to the nonvolatile memory.
The memory system includes a volatile memory in addition to a storage memory. The memory system caches translation information in the volatile memory during operation and uses the translation information cached in the volatile memory. A technique of efficiently caching translation information in the volatile memory is required for the memory system.